Title : Exogenous Gamma Amino Butyric Acid Application Improved the Performance of Fragrant Rice under Water Deficit Conditions
Water deficit conditions causes physiological and biochemical interventions in crop plants; however, gamma amino butyric acid (GABA) may induce tolerance in crop under water stress conditions. The present study was comprised of two fragrant rice varieties i.e., Super Basmati and Basmati-515, two water levels i.e., 100% and 50% field capacity, and four GABA levels i.e., 0 (control), 1, 1.5 and 2 mM. Rice seedlings (30 days old) were transplanted into pots in July 2018 and drought stress was induced after 35 days of transplanting. Results depicted that the GABA treatment, water levels and rice varieties significantly affected the biochemical, physiological and yield attributes. GABA application significantly improved total soluble proteins, total free amino acids, peroxidase, catalase and anthocyanin and reduced hydrogen peroxide in two rice cultivars under drought stress. Data also revealed positive effect of GABA on physiological, yield, and yield indices in two rice varieties under limited water supply. Grain yield was increased up to 31% under well-water and 37% in water stress conditions by the application of GABA in Super Basmati compared with control, whereas in Basmati-515, the grain yield was increased up to 27% and 28% in well water and water stress treatment, respectively. Higher grain yield indicated that GABA induced tolerance in Super Basmati subjected to drought stress. Overall, GABA improved the performance of fragrant rice under water deficit conditions.